In general, a mammography device is a radiography device used to diagnose a breast cancer in an early stage, and acquires a two-dimensional image for diagnosing abreast cancer by causing X-rays to pass through a breast of an examinee with a predetermined dose and detecting the dose of transmitted X-rays using an X-ray sensitive film.
In recent years, a mammography device employs a method of digitally acquiring a two-dimensional image using an image sensor instead of the X-ray sensitive film. Such a mammography device has a structure in which a breast pressing member is interposed between an X-ray generator and a digital X-ray detector so as to cause the breast pressing member to press a breast for radiography in a state where the breast is placed on the digital X-ray detector.
FIG. 1 is a diagram schematically illustrating a configuration of a conventional mammography device 100. As illustrated in the drawing, the mammography device 100 includes a main body 110, a gantry 120, an X-ray generator 130, a pressing panel 140, and an X-ray detector 150.
The main body 110 is formed of a rectangular housing and is provided with an input device for operating the mammography device 100 and a display device for displaying an image. The main body 110 supports the gantry 120.
The gantry 120 is disposed on one side surface of the main body 110 so as to adjust the height thereof depending on the height of an examinee.
The X-ray generator 130 includes an X-ray source for emitting X-rays and is located at an upper end of the front surface of the gantry 120 so as to vertically irradiate the X-rays toward the X-ray detector 150 on which a patient's breast placed.
The pressing panel 140 is disposed between the X-ray generator 130 and the X-ray detector 150. The pressing panel 140 is movable up and down along a guide groove formed in the vertical direction on the front surface of the gantry 120. The pressing panel 140 provides a function of pressing a patient's breast against the top surface of the X-ray detector 150 disposed at the lower end of the front surface of the gantry 120.
The X-ray detector 150 converts X-rays, which have been generated by the X-ray generator 130 and have passed through a breast, into electrical signals and makes an image.
In such a mammography device 100, the X-ray detector 150 employs a high-contrast image sensor with a pixel size of 70 μm to 100 μm. However, such a high-contrast image sensor is advantageous for detecting an accurate size of a cancer, but has a limit in detecting a very small possible lesion. In general, since a very small possible lesion has a size of 50 μm or less, a high-definition sensor with a pixel size of 50 μm or less is required. However, the X-ray detector 150 in the conventional mammography device 100 employs only a high-contrast image sensor with a pixel size of 70 μm to 100 μm and thus has a problem in that a small possible lesion cannot be detected.
On the other hand, the above-mentioned conventional mammography device 100 can acquire only a two-dimensional (2D) image and thus has a trouble that a breast CT scanning device should be used to acquire a three-dimensional image which can enable ascertaining of an accurate position of a lesion.
In this way, when a breast CT scanning operation is carried out to acquire a three-dimensional image, a particular CT scanning device is used, which is very troublesome. In addition, since a three-dimensional image is captured in a state where a patient lies down and the breast is not pressed, there is a problem in that an accurate image cannot be acquired.